Patent · US Expired

Furnace adapted to produce lime for use in downstream flue gas desulfurization process

US6391266B1 · kind B1 · utility

5Cited by
17References
15Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 14, 2000
Grant dateMay 21, 2002
Priority date
Expiry dateAug 14, 2020

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC04B2290/20
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A limestone furnace calcination process involves injecting finely divided limestone particles into a zone in a furnace at which the temperature of the flue gas stream, as it passes through the zone, is above the minimum calcination temperature and below the minimum effective quicklime utilization/sulfation temperature. In conventional furnaces, the minimum calcination temperature, or the calcium carbonate decomposition temperature, ranges from about 1,365 to 1,430° F. The minimum effective quicklime utilization/sulfation temperature refers to the temperature below which the rate of quicklime sulfation of the lime produced by calcination of the limestone is sufficiently slow to result in negligible calcium sulfate formation on the resultant lime, and in conventional furnace applications ranges from 1,600 to 1,800° F. The zone is preferably sized such that limestone particles injected therein will remain at a temperature above the minimum calcination temperature, as the particles are carried downstream, for a period sufficient for substantially complete calcination of the limestone particles to lime while minimizing reactions between the resultant lime particles and sulfur di…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.